Does smoking have an impact on the immunological response to COVID-19 vaccines? Evidence from the VASCO study and need for further studies

OBJECTIVES

The aim of this study was to investigate the possible impact of smoking on the humoral response to the BNT162b2 mRNA COVID-19 vaccine (also known as the BioNTech-Pfizer COVID-19 vaccine).

STUDY DESIGN

A longitudinal sero-epidemiological study was conducted in sample of Italian healthcare workers (HCWs).

METHODS

HCWs who were administered two doses of the BNT162b2 mRNA vaccine, 21 days apart, between December 2020 and January 2021, were invited to undergo multiple serology tests to identify SARS-CoV-2 S-RBD-specific immunoglobulin G (IgG) antibodies. Participants also responded to questions about their smoking status (i.e. current smokers vs non-smokers) in a survey.

RESULTS

Sixty days after the completion of the vaccination cycle, serological analyses showed a difference in vaccine-induced IgG titre between current smokers and non-smokers, with median antibody titres of 211.80 AU/mL (interquartile range [IQR] 149.80-465.50) and 487.50 AU/mL (IQR 308.45-791.65) [P-value = 0.002], respectively. This significant difference in vaccine-induced IgG titres between current smokers and non-smokers remained after adjusting for age, sex, and previous infection with SARS-CoV-2.

CONCLUSIONS

This study observed that vaccine-induced antibody titres decrease faster among current smokers than non-smokers. Further research to investigate the impact of smoking on the immunological response to COVID-19 and non-COVID-19 vaccines is required.

Use of antidepressants during COVID19 outbreak: a real-world drug-utilization study

Background

Lockdown measures implementation (LMI) to prevent COVID19 disease diffusion was associated to increased depression and anxiety cases. The main aim was to evaluate whether LMI affected prevalence and incidence of antidepressants (ADs) use, and ADs treatment interruption (TI) in the general population.

Methods

Adults (≥18 years) with at least 1 dispensing of ADs between 01/01/2019-26/09/2020 were selected from a regional Italian healthcare administrative database. Patients presenting an AD dispensing in the year preceding the first observation were considered as prevalent otherwise as incident users. We divided the studied period into 3 parts: pre-lockdown (01/01/2019-08/03/2020), lockdown (09/03/2020-14/06/2020) and post-lockdown (15/06/2020-27/09/2020). The weekly prevalence (WP) and incidence (WI) per 10,000 inhabitants were compared among periods. Incidence of TI (no dispensing refill within 30 days of the end of its validity) was computed among prevalent AD users.

Results

The WP (mean of 552.3 per 10,000 pre-lockdown vs 505.5 lockdown phase; relative change: -9%) and WI (5.2 vs 3.7; -29%) of ADs use decreased after LMI. During the post-lockdown phase WP (505.5 vs 495.9; -2%) decreased whereas the WI (3.7 vs 4.3; 16%) slightly increased in relation to the lockdown period, although differences were not statistically significant. Conversely, the incidence of TI increased during lockdown (344.7 vs 384.3; 12%) and post-lockdown (384.3 vs 394.2; 3%) periods, even not always statistically significant.

Conclusions

Our analysis showed a reduction of ADs use during the early phase of lockdown. Several factors might have impacted on the observed phenomenon (i.e, patient reluctance to start new AD treatment). Considering the mutation of the virus and the potential waves that might occur in the next months, a continuous monitoring of the impact of COVID19 on mental diseases onset and treatment adherence are suggested.

Key messages

In Italy, the implementation of lockdown measures was followed by a reduction in antidepressants use, even though evidences are that diagnoses of psychiatric disorders increased.

Future studies should monitor if these phenomena led to an increase in adverse events potentially correlated with inappropriate treatment of depression.

Post-stroke epilepsy and mortality: an observational study on healthcare administrative database

Background

Post-stroke epilepsy (PSE) has been associated with hospitalization and increased mortality risk. So far, evidence on PSE and mortality risk is lacking. Therefore, this study aimed to evaluate the association between PSE and mortality in different type of stroke.

Methods

A retrospective observational study was conducted using healthcare administrative databases of Lombardy, a northern Italian region (16.4% of the Italian population). Patients aged 40 years or older admitted to the hospital between 1/1/2004 and 31/12/2008 with diagnosis of hemorrhagic (HS)- or ischemic (IS)- stroke were included. Diagnosis of seizure/epilepsy was identified by using discharge ICD9-CM codes, exemption code or use of antiepileptic drugs. This date was considered the index date. For each stroke cohort case of PSE was matched with 2 non post-stroke epileptic (PNS) individuals. Demographic and clinical characteristics were compared between PSE and PSN among the stroke cohorts. Cox proportional regression model was used to estimate the hazard ratio (HRs) and 95% confidence intervals (95%CI) of mortality.

Results

In the observed period, 13,749 of patients (4,583 PSE Vs 9,166 PSN) had IS and 4,875 (1,625 PSE Vs 3,250 PNS) had HS. Individuals were ≥75-year-old with no difference among cohorts (p value >0.9). Similarly, no differences were observed for gender (p = 1.00) and Charlson'comorbidity index (p = 1.00). Early seizure occurred in 15% of ischemic cohort and 20% of hemorrhagic one. Differences in antithrombotic drug use were observed among PSE and PSN in IS (p = 0.009) and HS cohort (p = 0.03). In ischemic cohort PSE was positively associated with increased mortality risk (HRadj: 1.67; 95%CI: 1.57-1.79), whereas no significant result was observed in hemorrhagic cohort (1.06; 0.94-1.20).

Conclusions

This study demonstrated a twofold increased risk of mortality in IS cohort. Further studies need to deeply characterize possible association between PSE and mortality in HS individuals.

Key messages

Occurrence of seizure/epilepsy in ischemic post-stroke patients represents a risk factor for morality. New studies need to clarify the contrasting result observed for hemorrhagic PSE patients.

Dipeptidyl peptidase-4 inhibitors and heart failure: Analysis of spontaneous reports submitted to the FDA Adverse Event Reporting System

BACKGROUND AND AIMS

We tested the possible association between dipeptidyl peptidase-4 inhibitors (DPP-4-I) use and heart failure (HF) occurrence by assessing the publicly available US-FDA Adverse Event Reporting System (FAERS).

METHODS

FAERS data reporting HF and DPP-4-Is use in the period from the fourth quarter of 2006 through 2013 were extracted, using the Standardized MedDRA Query "Cardiac failure". Disproportionality (case/non-case method) was implemented by calculating Reporting Odds Ratios (RORs) with 95% Confidence Interval (CI): (1) exploratory analysis on the entire FAERS (using rosiglitazone as positive control); (2) consolidated analyses by therapeutic area (within antidiabetics), correcting for event- and drug-related competition bias and adjusting for co-reported drugs as confounders.

RESULTS

HF during DPP4-I use was recorded in 390 reports (4.4% of total reports). In exploratory analysis, statistically significant ROR emerged for DPP-4-I as a class (ROR = 1.17; 95% CI = 1.05-1.29), saxagliptin (1.68; 1.29-2.17), vildagliptin (2.39; 1.38-4.14), and rosiglitazone (13.98; 13.30-14.70). In consolidated analyses, the ROR for saxagliptin (2.60; 1.92-3.50) and vildagliptin (4.07; 2.28-7.27) increased, and became also significant for sitagliptin (1.61; 1.40-1.86). Concomitant drugs were reported in more than 50% of cases; the adjusted RORs of saxagliptin (2.30; 1.70-3.10), vildagliptin (3.15; 1.76-5.63), and sitagliptin (1.48; 1.28-1.71) were nonetheless significant.

CONCLUSION

FAERS data are consistent with clinical studies on a possible association between saxagliptin and HF. The disproportionate reporting of HF with sitagliptin, conflicting with a recent phase IV trial, suggests that cardiovascular safety requires close post-marketing vigilance by clinicians of individual DPP-4-I in the community until the issue of class effect is solved.